The Physics of the Email Universe

We talk a lot about rules and best practices in email, but we’re mostly talking about “squishy” rules-of-thumb that are based on simplified models of how mail systems, spam filters, recipients, postmasters and blacklist operators behave. They’re the biology, ecology and sociology of the email ecosystem.
There’s another set of rules we tend to only mention in passing, if at all, though. They’re the steely, sharp-edged laws that control the email universe. They’re the RFCs that define how email works and make sure that mail systems written by hundreds of different people across the globe all work and all interoperate with each other.
Building a message from Zeros and Ones
RFC 5322 – Internet Message Format
This tells you everything you need to know about crafting a simple email, with a subject line, a sender, some recipients and a simple plain-text message. It’s also the foundation of all fancier emails. If you’re creating emails, this is where to start.
A little more than plain ASCII
RFC 2047 – MIME Part 3: Message Header Extensions for Non-ASCII Text
RFC 2047 is one small part of the MIME (Multipurpose Internet Mail Extensions) suite of protocols that allow you to include pictures and attachments and prettily formatted text and comic sans in your email. This part defines how you can put things other than the plainest of plain text in your subject lines or in the “friendly from” of your message. It’s what allows you to put Hiragana, or Cyrillic, or umlauts, or cedillas, or properly matched double quotes in your subject line. It also let’s you put hearts or smiley faces or other little pictograms there – but nothing this useful is going to be perfect.
RFC 2045 – MIME Part 1: Format of Internet Message Bodies
This shows how to send an image, or a plain text mail in a different character set, or an HTML mail. It doesn’t tell you how to send plain text and HTML, or to send HTML with embedded images, or a message with an attached document. For that you need…
Finally, Modern Email
RFC 2046 – MIME Part 2: Media Types
This builds on RFC 2045 to allow you to have many different chunks in a message – this is what you need if you want to send “proper” HTML mail with a plain text alternative, or if you want embedded images or attachments.
Getting From A To B
RFC 5321 – Simple Mail Transfer Protocol
A message isn’t much use unless you send it somewhere. RFC 5321 explains the mysteries of actually sending that message over the wire to the recipient. If you need to know about the different phases of a message delivery, what “4xx” and “5xx” actually mean, why there’s not really any such thing as a hard or soft bounce defined, just temporary or permanent failures, or anything else about actually sending mail or diagnosing mail delivery, this is your starting point.
The Rest Of The Iceberg
I’ve only touched on the very smallest tip of the email iceberg here. There’s much, much more – both in RFCs and ad-hoc non-RFC standards. If you’re interested in more, this is a decent place to start.

Related Posts

The answer is 42

I continually run into companies that don’t really have a goal or understanding of their email marketing program. They’ve never really asked questions about how they’re using email or even why email is the right answer. Lots of companies are also diving head first into email marketing or the social media craze without having thought about what their goals are and what they want to happen.
What regularly ends up happening to companies that jump in without a clear goal is they get into a situation where their delivery is bad. Then they read a lot of best practice advice on the net and try to implement all of it. Sometimes that works, but other times it doesn’t. Finally they hire me or another consultant to help them sort out where it all went pear shaped.
My consulting isn’t about rote recitation of common best practices. Instead, I want to know about a client’s business and what they think about email.  The most frequent question I ask clients is: How does email fit into your business? What are your goals for your business? What is your value proposition?
Some of my clients can’t answer these question. They just tell me they want to use email and they don’t know what they’re doing and that’s why they hired me. Well, I can help them successfully send email, but I can’t help them decide what role email plays in their business. Those are the decisions my client needs to make. I can’t set their business goals for them.
When was the last time you actually sat down and just thought about your business goals? I know that sometimes it’s hard to find the time to look at your business and where it’s going. “Think about it? I’m too busy doing it!” But every business person needs to look at their business goals.
Once you’ve thought about your goals, think about your email marketing program. Is email helping you to reach those goals? How?
If you’ve reached your current business goals, what are your next ones? And how does email fit into those goals?
Sure, having an answer is good, but are you actually asking the right question?

Read More

Spam lawsuit guide

Mailchimp has released a guide to spam lawsuits with advice on how to not be a target.
I had the pleasure of meeting some of the Mailchimp legal staff last year when I was down there to do on-site training for their abuse desk employees. I was quite impressed with them and their understanding of privacy and email issues.

Read More

We lie more in email than in person

People are more prone to lie over email than face to face.

Read More